120,000 Pounds of Cosmic Dust Floats Down From Space Every Day

NASA may be endlessly fascinated with microbial life on far-flung moons in our solar system or testing powerful rocket boosters that will propel humanity off its ancestral home, but there's still tons we don't know about our own planet—and cosmic dust is one of those mysteries. » 3/12/15 2:09pm 3/12/15 2:09pm